"value" is an ambiguous word. I think you understand it as "something people are willing to put money into", which certainly covers gambling.

Another definition of "value" is something which increased the economic output, a positive-sum game. Thus gambling (which is zero-sum) does not create value.

Derivatives do create value in the second sense, in that they can be used to protect against risk, thus creating value (or allowing the creation of value). Yes, they can also be used for the equivalent of gambling, but they have additional uses.

> An NFT marketplace is a similar to gambling or derivatives.

Derivatives have real utility.

Just to be clear, gambling is a net societal negative. For every dollar that goes in, less than a dollar in income comes out. It's going to happen, but let's not pretend that it's value-creating.